1. Field of the Invention
This invention relates generally to an entry tap valve for permitting a pressurized pipe to have a leak detector inserted thereinto at an appropriate spot therealong in order to ascertain and locate a leak or leaks in the pipe while it is still under pressure.
2. Description of the Prior Art
A common problem with known type tap and entry valves is that they can not be installed and/or used while the pipe being tapped is still pressurized. Also, often they fail to function properly and/or leak fluid therefrom during use.
Another common problem of known tap valves is that they are not designed or structured so as to permit easy or quick entry therethrough of a detector head unit for leak detector apparatus. That is, they either have too small an entry passageway and/or have obstructions therewithin to prevent easy passage of such a detector head.
A still further problem is that the known type valve taps leave much to be desired in simplicity and/or usefulness. The materials generally used for such taps fail to meet all of the desired performance qualities, and yet still are relatively expensive.
Still another common problem of known tap valves is that they are not designed or structured so as to permit entry therethrough of a deflecting guide shoe for the detector head unit of a leak detector apparatus.
Existing prior patents which may be pertinent to this invention are as follows:
______________________________________ 1,263,929 (GREAT BRITAIN) Tew et al August 7, 1974 3,691,819 Guest Sept. 19, 1972 4,073,302 Jones Feb. 14, 1978 4,418,572 Prange Dec. 6, 1983 ______________________________________
The Tew et al (Great Britain) patent discloses a gas main 1 having a standpipe 2 with cover (not shown) for entry to the main by a hose 3 with nozzle assembly 4. A spoon 5 having a curved end 6 helps guide the nozzle and hose in a manner similar to the deflecting guide shoe of the present invention. However, the rest of the device is entirely different from the entry tap structure of the present invention.
The Jones (U.S. Pat. No. 4,073,302) device is for cleaning sewer and other pipes. A sewer pipe 12 is shown having an entry standpipe 15 with an angled upper edge 16 for guiding hose 70. However, the overall structure is quite different from applicant's invention.
The Guest U.S. Pat. No. 3,691,819 discloses a detector pig which is caused to move through a pipe by sel-propelling structure, while the Prange U.S. Pat. No. 4,418,572 discloses a sewer pipe tester. However, neither the Guest nor the Prange patents disclose the entry tap structure for their respective detector-tester apparatus, and therefor do not teach anything like the present invention.
None of the known prior art devices offer the new and novel features of the present invention.